EDIT: I'll try to tackle what's what...?
Originally Posted by danhese007
So Nikkei did an interview with Mark Cerny and apparently they considered using eDRAM in PS4 but they dropped it because while:
He then states 4 of many bespoke supercharged parts of PS4's architecture.
"For example, if we use eDRAM (on-chip DRAM) for the main memory in addition to the external memory, the memory bandwidth will be several terabytes per second. It will be a big advance in terms of performance."
"However, in that case, we will make developers solve a puzzle, 'To realize the fastest operation, what data should be stored in which of the memories, the low-capacity eDRAM or the high-capacity external memory?'" he said. "We wanted to avoid such a situation. We put the highest priority on allowing developers to spend their time creating values for their games."
As for the "supercharged" parts, or the parts that SCE extended, he said, "There are many, but four of them are representative." They are (1) a structure that realizes high-speed data transmission between the CPU and GPU, (2) a structure that reduces the number of times that data is written back from the cache memory in the GPU, (3) a structure that enables to set priorities in multiple layers in regard to arithmetic and graphics processing and (4) a function to make the CPU take over the pre-processing to be conducted by the GPU.
1) Is the GNB (Graphics North Bridge) that allows for high instant access using the "Onion", "Garlic", and "Onion+."
2)...maybe still part of GNB?
3)Those extra Asynchronous Compute Engines